[albert20260301]

Summary

• Use ubuntu-24.04 for Linux jobs instead of the moving ubuntu-latest image.
• Pin the existing third-party action references to their resolved 40-character commit SHAs, keeping the original references in comments.
• Keep job behavior, permissions, Python versions and release conditions unchanged.

Verification

• Workflow policy validator, YAML parsing and final diff checks pass.
• 20 focused Ibis/query-error/Parquet tests, Ruff and Mypy pass locally.
• Quoted-NULL schema replay reproduces the original failure; explicit BIGINT cast reaches the remote ApiError.
• Separate test-only test(ibis): type error expression before checking propagation #34 ran all 43 tests successfully on Python 3.12 against the real mock, but Ubuntu 26.04 cannot provision Python 3.9, cancelling the remaining matrix. No full-matrix success claim.

CI diagnosis and correction

The initial pinned-runner CI failed one Python 3.11 test (42 passed / 1 failed); the other five matrix jobs were cancelled. An untyped error expression was described as quoted "NULL", rejected by Ibis before remote execution. This PR now includes the focused test correction from #34: cast the always-failing expression to BIGINT, retaining discovery and remote-error assertions without changing production type guards.

The unpinned main workflow separately fails setup-python on Ubuntu 26.04 for Python 3.9. Keeping the test correction with the already-proposed Ubuntu 24.04/action pins allows the full supported matrix to run. New CI from the substantive test commit must pass before this draft is marked ready. No workflow reruns or artificial trigger commits.

[albert20260301]

@fvaleye, please review the runner/action pins and the focused Ibis test correction. Combined CI is green across Python 3.9–3.14, lint/types and title validation (run).

The cast lets the existing integration test reach the remote error instead of rejecting an unknown quoted-NULL schema locally; production type guards are unchanged. The separate #34 attempt also confirmed Ubuntu 26.04 cannot provision Python 3.9, so the existing Ubuntu 24.04 pin is needed for the supported matrix.

If there is no response by November 5, I’ll leave this PR open and wait; no merge or repeat ping. After this merges, #34 can be retired as redundant.